The present invention relates generally to ink printers, the inks used in such ink printers, and the apparatus and method for delivering the ink is into the printer.
Solid ink or phase change ink printers conventionally receive ink in a solid form and convert the ink to a liquid form for jetting onto a receiving medium. The printer receives the solid ink either as pellets or as ink sticks in a feed channel. With solid ink sticks, the solid ink sticks are either gravity fed or spring loaded through the feed channel toward a heater plate. The heater plate melts the solid ink into its liquid form. In a printer that receives solid ink sticks, the sticks are either gravity fed or spring loaded into a feed channel and pressed against a heater plate to melt the solid ink into its liquid form. U.S. Pat. No. 5,734,402 for a Solid Ink Feed System, issued Mar. 31, 1998 to Rousseau et al.; and U.S. Pat. No. 5,861,903 for an Ink Feed System, issued Jan. 19, 1999 to Crawford et al. describe exemplary systems for delivering solid ink sticks in a phase change ink printer.
An ink stick for use in a solid ink feed system of a phase change ink jet printer is formed of an ink stick body. The ink stick body includes a bottom, a rear, and at least one key element formed through the bottom of the ink stick body for permitting the ink stick to pass a portion of the feed system having a corresponding key. In particular, the key element permits the ink stick to be fully inserted into a keyed feed channel of the solid ink feed system if the key element matches the key in the feed channel.
A method of feeding solid ink to the melt plate of a phase change ink printer includes placing an ink stick adjacent an insertion end of a solid ink feed channel. The other end of the feed channel is adjacent the melt plate, and the feed channel has a feed channel key in the insertion end. The method further includes inserting the ink stick into the feed channel if the ink stick has a key element corresponding to the feed channel key, or blocking the ink stick from full insertion if the ink stick does not have a key element corresponding to the feed channel key.